Hair treatment formulations containing a water-insoluble polymer having a glass transition temperature of -20° C. to 70° C.

ABSTRACT

A process for treating hair by applying thereto a composition in the form of an aqueous dispersion of a water-insoluble polymer having a glass transition temperature of -20° C. to +70° C. wherein the water-insoluble polymer is formed from monomers selected from the group consisting of esters of acrylic acid, esters of methacrylic acid and styrene, and the composition further contains a water-soluble polymer.

FIELD OF THE INVENTION

This invention relates to hair treatment formulations in the form ofaqueous dispersions of special polymers.

An attractive-looking hairstyle is today generally regarded as anessential part of a groomed appearance. In the context of currentfashion trends, "chick" hairstyles are always those which, with manytypes of hair, can only be created and maintained for prolonged periodsusing certain setting agents.

These setting agents, which are generally polymeric compounds, may beincorporated in typical hair cleaning and conditioning formulations. Inmany cases, however, it is of advantage to use them in the form ofspecial formulations, such as setting lotions or hair sprays.

Now, there have recently been a number of developments in the haircosmetics field which have created a demand for new setting agents orrather new types of formulation. Many of these developments are notattributable to performance-related disadvantages or inadequacies ofknown formulations, but for example to environmental factors, to legalrequirements or to other "non-technical" causes.

Accordingly, there is a need to develop corresponding formulations whichmeet consumer expectations in regard to their performance properties,for example spray behavior and drying time in the case of hair sprays.

In particular, there is an increasing demand for a change fromformulations based on volatile organic compounds, for example alcohols,to water-based formulations.

It has now been found that hair treatment formulations in the form ofaqueous dispersions of certain water-insoluble polymers, whichadditionally contain a dissolved polymer, are eminently suitable for anumber of applications.

DESCRIPTION OF THE INVENTION

Accordingly, the present invention relates to hair treatmentformulations containing typical cosmetic ingredients in the form of anaqueous dispersion of an insoluble polymer, characterized in that thepolymer has a glass transition temperature of -20 to +70° C. and isessentially formed from monomers selected from the group consisting ofesters of acrylic acid, esters of methacrylic acid and styrene and inthat the hair treatment formulation additionally contains awater-soluble polymer.

Hair treatment formulations in the form of aqueous solutions oremulsions of polymers containing acrylate monomers are known, forexample, from International patent applications WO 94/02112 and WO/01079and from European patent application O 590 604.

In addition, the use of water-soluble or water-dispersiblepoly-condensates with glass temperatures above +20° C. in hair treatmentformulations is known from DE-OS 42 24 761.

Finally, hair sprays in the form of water-based polyester dispersionsare known from publication CB-14B of the Eastmann Chemical Company.These hair sprays have the disadvantage that, at high polymerconcentrations, the nozzles of the applicator often become blocked afteronly a short time, particularly in the case of pump sprays. Accordingly,these polymers can only be used in relatively low concentrations inconsumer products so that, when the necessary quantities of polymer areapplied to the hair, a large amount of water is applied at the sametime.

However, none of the cited documents makes any reference to theparticularly advantageous properties of the formulations according tothe invention.

The hair treatment formulations according to the invention are presentin the form of aqueous dispersions and contain an insoluble polymer.

Aqueous dispersions in the context of the present invention aredispersions of which the outer phase consists predominantly of water.The outer phase may additionally contain other water-miscible solvents,for example ethanol and isopropanol. These other solvents are present inquantities of at most up to 10% by weight, based on the formulation as awhole. In a preferred embodiment, the outer phase contains water as solesolvent. Another preferred embodiment contains no more than 5%, based onthe formulation as a whole, of other solvents in the outer phase.

In exceptional cases where an only sparingly water-soluble nonionicpolymer is to be additionally incorporated in the formulation, thecontent of other solvents may be up to 20%. In cases such as these,however, it is absolutely essential to ensure that the dispersion is notdestabilized. Such destabilization is prevented inter alia by not addingpure or 96% alcohol in the preparation of the formulation. The alcoholcomponent should only be added in the form of a solution with aconcentration of 50% or less.

In the context of the invention, a polymer is insoluble if less than 1%by weight dissolves in water at room temperature.

The water-insoluble polymers used in accordance with the invention haveglass transition temperatures of -20° C. to +70° C. Polymers with glasstransition temperatures of -10° C. to +50° C. and, more particularly,from +10° C. to +30° C. are preferred.

The water-insoluble polymers used in accordance with the inventionconsist for the most part, i.e. at least 80% by weight, based on thepolymer, of esters of acrylic acid and/or methacrylic acid and/orstyrene.

Esters of acrylic and methacrylic acid suitable for the purposes of theinvention are any known esters of these acids with linear and branched,saturated and unsaturated aliphatic alcohols, aromatic alcohols andaliphatic-aromatic alcohols. Esters with linear and branched, saturatedand unsaturated aliphatic alcohols containing 1 to 22 carbon atoms arepreferred. Examples of such alcohols are methanol, ethanol, n- andisopropanol, n- and iso-1-butanol, n-1-pentanol, n-1-hexanol,n-1-heptanol, n-1-octanol, n-2-octanol, n-1-decanol, n-1-dodecanol(lauryl alcohol), myristyl alcohol, cetyl alcohol, stearyl alcohol,behenyl alcohol, oleyl alcohol and linoleyl alcohol. Particularlypreferred alcohols contain 1 to 6 and, more particularly, 1 to 4 carbonatoms.

Esters of acrylic and methacrylic acid with the correspondingalkoxylated, more particularly ethoxylated, alcohols may also be used inaccordance with the invention, but are less preferred. The degrees ofalkoxylation may be from 1 to about 10.

Styrenes in the context of the present invention are also compoundswhich contain a short-chain alkyl group, more particularly a methylgroup, at the α C atom of the vinyl group. The content of styrene groupsin the polymer is preferably limited to less than 70% by weight, basedon the polymer, because otherwise difficulties could be involved inobtaining polymers with glass temperatures in the range mentioned.

One particular advantage is that polymers consisting only of a fewmonomers may be used in accordance with the invention. Thus,formulations containing homopolymers or copolymers of only two monomershave surprisingly good properties. Accordingly, it may be preferable touse such homopolymers or copolymers for the purposes of the teachingaccording to the invention.

In a preferred embodiment, therefore, the water-insoluble polymerscontain no other structural elements apart from the acrylates,methacrylates and styrenes, impurities of the monomers andchain-terminating compounds not being regarded as further structuralelements.

However, it has been found that polymers containing up to 20% by weightand, more particularly, up to 10% by weight of other structural elementsmay also be used in accordance with the invention. The other structuralelements in question may be:

acrylamides and methacrylamides,

acrylic acid, methacrylic acid and alkali metal, alkaline earth metal,aluminium, ammonium and alkylolammonium salts thereof,

crotonic acid, esters and alkali metal, alkaline earth metal, aluminium,ammonium and alkylolammonium salts thereof,

vinyl and allyl compounds,

aminofunctional monomers.

In general, the advantages according to the invention were only observedwith those polymers in which the percentage content of other structuralelements was limited to less than 5% by weight, based on the polymer. Itwas also found that, where ionic structural elements were included, itwas of advantage for only cationic or only anionic structural elementsto be represented in the polymer. These polymers had distinctly betterproperties than those in which both anionic and cationic structuralelements were represented.

In selecting the monomers and the other structural elements, if any, itis absolutely essential to ensure that the glass temperature is in therange from -20° C. to +70° C. The expert is in a position to make thenecessary choice in advance without any difficulty on the basis of theknown relationships between the glass temperatures of the particularhomopolymers and the corresponding copolymers. In the case of polymerscontaining other ionic structural elements, it is essential to ensurethat solubility does not increase too much in order to avoid theresulting disadvantages.

The average molecular weights of the polymers used in accordance withthe invention are generally in the range from 20,000 to 2,000,000,molecular weights in the range from 50,000 to 500,000 having proved tobe particularly advantageous. The possibilities for obtaining molecularweights in a required range in the synthesis of polymers are well knownto the expert.

The hair treatment formulations according to the invention preferablycontain the insoluble polymer in quantities of 0.1 to 30% by weight and,more preferably, in quantities of 1 to 20% by weight, based on theformulation as a whole, in dependence upon the type of hair treatmentformulation which is not limited in any way.

Even at relatively high concentrations, i.e. at concentrations aboveabout 10%, the formulations according to the invention are distinguishedfrom formulations containing dissolved polymers by very low viscosities.Since it is thus possible to prepare formulations with the highpercentage contents of polymers mentioned, the necessary quantity ofpolymer can be applied to the hair with a comparatively small quantityof water, so that the drying time of formulations remaining on the hairremains in an acceptable range.

The removability in particular of the hair treatment formulations bywashing out is distinctly increased if they additionally containwater-soluble polymers. The term "water-soluble" in the context of theinvention is understood to mean that the quantity of polymer present inthe hair treatment formulation according to the invention is soluble inwater at room temperature. In general, distinctly more than 1% by weightof these polymers, which are mentioned in detail hereinafter, is solublein water.

In a preferred embodiment, the water-soluble polymers are present in thehair treatment formulations according to the invention in quantities of0.05 to 5% by weight, based on the formulation as a whole. In manycases, quantities of only about 1% by weight or less, based on theformulation as a whole, are sufficient.

In another preferred embodiment, the water-soluble polymers are used inquantities of 1 to 20% by weight, based on the dispersed insolublepolymer.

This water-soluble polymer may even be used as a stabilizer in theemulsion polymerization of the insoluble polymers, i.e. may actually beadded during the preparation of the insoluble polymer. However, it isnormally added during the production of the hair treatment formulation.

Particularly preferred water-soluble polymers according to the inventionare nonionic, particularly where they are added during the production ofthe hair treatment formulation. Examples of suitable nonionic polymersare:

Polyvinyl pyrrolidones of the type marketed, for example, under the nameof Luviskol® (BASF).

Vinyl pyrrolidone/vinyl acetate copolymers of the type marketed, forexample, under the name of Luviskol® (BASF). Luviskol® VA 64 andLuviskol® VA 73 are preferred nonionic polymers.

Cellulose ethers, such as hydroxypropyl cellulose, hydroxyethylcellulose and methyl hydroxypropyl cellulose, of the type marketed, forexample, under the names of Culminal® and Benecel®) (AQUALON).

Suitable amphoteric polymers are, for example, the octylacrylamide/methyl methacrylate/tert.butylaminoethylmethacrylate/2-hydroxypropyl methacrylate copolymers obtainable underthe names of Amphomer® and Amphomer® LV-71 (DELFT NATIONAL), althoughtheir use is generally confined to neutral or alkaline formulations.

Suitable zwitterionic polymers are, for example, the polymers disclosedin German patent applications DE 39 29 973, DE 21 50 557, DE 28 17 369and DE 37 08 451. Acrylamidopropyl trimethyl ammonium chloride/acrylicacid or methacrylic acid copolymers and alkali metal and ammonium saltsthereof are particularly preferred zwitterionic polymers. Other suitablezwitterionic polymers are methacroyl ethyl betaine/methacrylatecopolymers which are commercially available under the name of Amersette®(AMERCHOL).

Anionic polymers suitable for the purposes of the invention are interalia:

Vinyl acetate/crotonic acid copolymers of the type marketed, forexample, under the names of Resyn® (NATIONAL STARCH), Luviset® (BASF)and Gafset® (GAF).

Vinyl pyrrolidone/vinyl acrylate copolymers obtainable, for example,under the name of Luviflex®) (BASF). A preferred polymer is the vinylpyrrolidone/acrylate terpolymer obtainable under the name of Luviflex®)VBM-35 (BASF).

Acrylic acid/ethyl acrylate/N-tert.butyl acrylamide terpolymers of thetype marketed, for example, under the name of Ultrahold® strong (BASF).

To secure the advantages according to the invention, the use of anionicpolymers is generally also limited to neutral or, more particularly,alkaline solutions.

Cationic polymers are only suitable as soluble polymers in exceptionalcases.

In cases where the water-insoluble polymer contains ionic groups, it hasproved to be appropriate for the water-soluble polymer to be nonionic orto have the same ionicity.

In some cases, a combination of dispersed anionic polymers and dissolvedanionic polymers has proved to be particularly advantageous. Inaddition, it is preferred in many cases to add the soluble polymer tothe otherwise completed formulation.

The other ingredients of the hair treatment formulations according tothe invention are dependent upon the type of hair treatment formulation.In principle, the formulations according to the invention encompass allknown types of hair treatment formulations such as, for example, settinglotions, hair sprays, styling gel, hair shampoos, hair rinses, hairconditioners, permanent wave sets and hair colorants.

Preferred hair treatment formulations according to the invention arethose which remain on the hair after application. These include inparticular setting lotions, hair sprays and styling gels. Formulationssuch as these may also be made up with a propellent to form a foamaerosol.

Other ingredients of the formulations according to the invention may be,for example,

anionic surfactants, such as for example fatty alkyl sulfates and ethersulfates,

cationic surfactants, such as for example quaternary ammonium compounds,

zwitterionic surfactants, such as betaines, for example,

ampholytic surfactants,

nonionic surfactants, such as for example alkyl polyglycosides andethoxylated fatty alcohols,

structurants, such as glucose and maleic acid,

hair-conditioning compounds, such as phospholipids, for example soyalecithin, egg lecithin and kephalins, and also silicone oils,

protein hydrolyzates, more especially elastin, collagen, keratin, milkprotein, soya protein and wheat protein hydrolyzates, condensationproducts thereof with fatty acids and quaternized protein hydrolyzates,

perfume oils, dimethyl isosorbide and cyclodextrins,

solubilizers, such as ethanol, isopropanol, ethylene glycol, propyleneglycol, glycerol and diethylene glycol,

dyes,

anti-dandruff agents, such as Piroctone Olamine and Zink Omadine,

other substances for pH adjustment,

active agents, such as panthenol, allantoin, pyrrolidone carboxylicacids and salts thereof, plant extracts and vitamins,

light stabilizers,

consistency regulators, such as sugar esters, polyol esters orpolyolalkyl ethers,

fats and waxes, such as spermaceti, beeswax, montan wax, paraffins andfatty alcohols,

fatty acid alkanolamides,

complexing agents, such as EDTA, NTA and phosphonic acids,

swelling and penetration agents, such as glycerol, propylene glycolmonoethyl ether, carbonates, hydrogen carbonates, guanidines, ureas andprimary, secondary and tertiary phosphates,

opacifiers, such as latex,

pearlescers, such as ethylene glycol monostearate and distearate,

propellents, such as propane/butane mixtures, N₂ O, dimethyl ether, CO₂and air and

antioxidants,

substantive dyes,

so-called primary and secondary intermediates as oxidation dyeprecursors,

reducing agents, such as for example thioglycolic acid and derivativesthereof, thiolactic acid, cysteamine, thiomalic acid andα-mercaptoethane sulfonic acid,

oxidizing agents, such as hydrogen peroxide, potassium bromate andsodium bromate.

The present invention also relates to the use of the formulationsaccording to the invention for treating keratin fibers, especially hair.

The following Examples are intended to illustrate the invention.

EXAMPLES 1. Production Examples

1.1 Polymer Dispersion 1

445 g of deionized water, 134 g of G-Cryl® 5000 (a water-solublecopolymer of an aromatic vinyl compound and acrylic acid with a glasstransition temperature of around 100° C. (Henkel)) and then, inportions, 30 g of a 25% aqueous ammonia solution were introduced into areaction vessel equipped with a stirrer, a heating system, a coolingsystem, a reflux condenser, a thermometer and a stirrable meteringvessel. The contents of the reaction vessel were then stirred at roomtemperature until a homogeneous opaque solution had formed. Afterrepeated evacuation and purging of the reaction vessel with high-puritynitrogen, 10 g of Dowfax 2A1 (4-dodecyl diphenyl ether disulfonatedisodium salt, 45% active substance in water (DOW)) were added and themixture was heated to 85° C. 3.5 g of ammonium peroxydisulfate dissolvedin 18 g of deionized water were then added, followed by the uniformintroduction over a period of 75 minutes of a mixture consisting of 185g of methyl methacrylate, 134 g of butyl acrylate and 15 g ofDehydrophen® 65 (nonylphenol +6.5 ethylene oxide (HENKEL)). Thetemperature of the mixture was kept just below +88° C. by externalcooling. When 80% of the monomer emulsion had been added, another 0.5 gof ammonium peroxydisulfate dissolved in 15 g of deionized water wereintroduced. After the monomer had been added, the mixture was stirredfor another 60 minutes at +85° C. After cooling to below +40° C., 10 gof polypropylene glycol (molecular weight around 1000; (DOW)) were addedto the resulting dispersion which was then filtered through a Perlon bagfilter with a mesh width of 80 μm.

The coagulate-free milky polymer dispersion had a viscosity of around3000 mPas. The glass temperature of the dispersed polymer was 20° C.

1.2 Polymer Dispersion 2

445 g of deionized water, 134 g of G-Cryl® 5000 (a water-solublecopolymer of an aromatic vinyl compound and acrylic acid with a glasstransition temperature of around 100° C. (Henkel)) and then, inportions, 30 g of a 25% aqueous ammonia solution were introduced into areaction vessel equipped with a stirrer, a heating system, a coolingsystem, a reflux condenser, a thermometer and a stirrable meteringvessel. The contents of the reaction vessel were then stirred at roomtemperature until a homogeneous opaque solution had formed. Afterrepeated evacuation and purging of the reaction vessel with high-puritynitrogen, 10 g of Dowfax 2A1 (4-dodecyl diphenyl ether disulfonatedisodium salt, 45% active substance in water (DOW)) were added and themixture was heated to 85° C. 3.5 g of ammonium peroxydisulfate dissolvedin 18 g of deionized water were then added, followed by the uniformintroduction over a period of 75 minutes of a mixture consisting of 123g of methyl methacrylate, 89 g of 2-ethylhexyl acrylate, 62 g ofstyrene, 45 g of butyl acrylate and 15 g of Dehydrophen® 65 (nonylphenol+6.5 ethylene oxide (HENKEL)). The temperature of the mixture was keptjust below +88° C. by external cooling. When 80% of the monomer emulsionhad been added, another 0.5 g of ammonium peroxydisulfate dissolved in15 g of deionized water were introduced. After the monomer had beenadded, the mixture was stirred for another 60 minutes at +85° C. Aftercooling to below +40° C., 10 g of polypropylene glycol (molecular weightaround 1000; (DOW)) were added to the resulting dispersion which wasthen filtered through a Perlon bag filter with a mesh width of 80 μm.

A coagulate-free milky polymer dispersion with a dry residue of 46.9%(as measured with a Mettler LP 15 drying balance for 1 hour at stage 10)and a Brookfield viscosity of around 1500 mPas (as measured with aBrookfield RTV viscosimeter at 20° C./20 r.p.m., spindle 2). Thedispersion had a pH value of 8. The glass temperature of the dispersedpolymer was 20° C.

1.3 Polymer Dispersion 3

396 g of deionized water and 1.5 g of Disponil® FES 993 (fatty alcoholpolyglycol ether sulfate with an active substance content of around 30%in water (HENKEL)) were heated to 82° C. in a reaction vessel equippedwith a stirrer, a heating system, a cooling system, a reflux condenser,a thermometer and a stirrable metering vessel. 0.5 g of potassiumperoxydisulfate dissolved in 12 g of deionized water were then added.The emulsion described in the following was then uniformly added over aperiod of 2 hours. The organic phase of the emulsion consisted of 152 gof butyl acrylate, 194 g of methyl methacrylate and 10 g of methacrylicacid while the aqueous phase consisted of 150 g of deionized water, 18.5g of Disponil® FES 993 and 1 g of potassium peroxydisulfate. Theemulsion was prepared by stirring in a metering vessel and was keptstable by continued stirring. During the addition, the temperature ofthe mixture was kept just below +85° C. by external cooling. After theaddition, the mixture was stirred for another 20 minutes at +85° C. 0.5g of potassium peroxydisulfate dissolved in 12 g of deionized water werethen added, followed by stirring for another 45 minutes at +85° C. Aftercooling to below +40° C., the dispersion was neutralized to a pH valueof 6.5 with around 5 g of 12.5% ammonia solution and was filteredthrough an 80 μm mesh Perlon bag filter.

A low-viscosity coagulate-free milky polymer dispersion with a dryresidue of 38.3% (as measured with a Mettler IR dryer for 1 hour atstage 10) and an average particle size of 115 nm was obtained. Thedispersed polymer had a glass temperature of around 20° C.

2. Performance Tests

2.1 Curl Retention Test

2.1.1. Test Procedure

The measurement was carried out on 5 hair tresses (#6925 of Fischbachund Miller; weight 0.5 g, length 28 cm) at 22° C./90% relative airhumidity.

The weighed dried tress was immersed in the polymer dispersion (5% byweight of polymer) to be investigated, uniform distribution beingensured by repeated immersion and removal. The excess polymer dispersionwas stripped off between the thumb and index finger and the tresses wereadjusted to a weight increase of around 0.3 g (based on the untreatedtress). The moist tress was then wound onto a spiral curler (diameteraround 7 mm) and dried overnight. The curled tress was then removed andhung for 24 hours at 22° C./90% relative air humidity.

The curl retention value is then calculated on the basis of thefollowing relation:

    c.sub.r =(l-l.sub.24)/(l-l.sub.0)·100

where

l is the length of the tress between the 1st and 5th wave centers in thestretched state

l₂₄ is the distance between the 1st and 5th wave centers after hangingfor 24 hours and

l₀ is the distance between the 1st and 5th wave centers immediatelyafter removal of the spiral curler.

Curl retention values of 58 and 60% were obtained with the dispersionsof Examples 1.2 and 1.3.

A high curl retention level is also obtained when the dispersions arevaried in regard to the Tg range mentioned. At very low Tg values, thefilms are too soft while, at very high Tg values, they are too brittle.In both cases, there is also a distinct deterioration in the curlretention values.

2.2.2. Removability by Washing

After 24 hours, hair tresses (#6923 of Fischbach und Miller; weightabout 2 g, length about 15 cm) which had been sprayed with theformulations to be investigated (1 g of spray containing 20% by weightof polymer) were washed with a surfactant solution (10% Texapon®N 28(sodium lauryl ether sulfate, 28% active substance in water (HENKEL)) inwater, dried and visually examined for residues.

The dispersions of Examples 1.1 and 1.2 were readily washed out.

The dispersion of Example 1.3 showed residues. By contrast, a dispersionwhich could be completely washed out was formed by addition of 1% ofLuviskol® VA 64 (vinyl acetate/vinyl pyrrolidone copolymer (BASF)).

2.2.3. Sprayability

All the dispersions were readily sprayable even at high polymerconcentrations (20%). The nozzles did not clog up even after prolongeduse.

3. Formulations

All Figures are Parts by Weight

3.1 Pump Spray

Panthenol 0.5

Perfume oil 0.2

Luviskol®VA 64¹ 1.0

20% dispersion of the polymer

according to Example 1.1 to 100

¹ Vinyl acetate/vinyl pyrrolidone copolymer (BASF)

3.2 Pump Spray

Panthenol 0.5

Perfume oil 0.2

20% dispersion of the polymer

according to Example 1.2 to 100

What is claimed is:
 1. A hair treatment composition consistingessentially of an aqueous dispersion containing 0.1% to 30% by weight ofa water-insoluble polymer having a glass transition temperature of -20°C. to +70° C. and an average molecular weight from 20,000 to 2,000,000,wherein at least 80% by weight of said water-insoluble polymer havingbeen formed from monomers selected from the group consisting of estersof acrylic acid, esters of methacrylic acid and styrene, 0.05% to 5% byweight of a water-soluble polymer, and the balance, water, based on theweight of the composition.
 2. A composition as in claim 1 wherein atleast 90% by weight of said water-insoluble polymer consists of monomersselected from the group consisting of esters of acrylic or methacrylicacid with C₁₋₂₂ alcohols and styrene, with the proviso that the contentof styrene units is not more than 70% by weight, based on the weight ofsaid polymer.
 3. A composition as in claim 1 wherein said esters ofacrylic and methacrylic acid comprise esters with C₁₋₆ alcohols.
 4. Acomposition as in claim 1 wherein said water-insoluble polymer containsat least two different monomers selected from esters of acrylic ormethacrylic acid and styrene.
 5. A composition as in claim 1 whereinsaid water-soluble polymer is nonionic.